Our comprehensive VVT testing ensures precise phase control, fast response, low leakage, and long-term durability across the full range of engine operating conditions.
This helps support engine power output, fuel efficiency, and emissions compliance.
Test Conditions
Test Oil: SAE 5W-30 or equivalent Temperature: 37°C ± 3°C
Oil Pressure: 100 kPa–980 kPa
Test Equipment
Dedicated inspection equipment
Performance test bench
Test Items and Acceptance Criteria
a. Lock-Pin Clearance
Test Requirement:
With no oil pressure applied, the phaser is driven by a motor. The measured angular movement must be within 0.1°–0.6°.
Potential Impact:
Insufficient lock-pin clearance may lead to product failure, while excessive clearance
may cause abnormal noise after installation.
b. Locking Pressure Verification
Test Requirement:
With the gear fixed, apply 0.2 bar oil pressure and measure angular movement using an angle encoder. The product is qualified when the angular movement is less than or equal to the lock-pin clearance.
Potential Impact:
Failure to meet the specified locking pressure requirement may prevent the product from operating properly after installation.
c. Unlocking Pressure Verification
Test Requirement:
With the gear fixed, apply 0.6 bar oil pressure and measure angular movement using an angle encoder. The product is qualified when the angular movement is greater than the lock-pin clearance.
Potential Impact:
The standard unlocking pressure is generally 0.2 bar–0.6 bar, except for certain applications. Non-compliance may result in slower response or, in severe cases,functional failure.
d. Friction Torque
Test Requirement:
With the gear fixed and oil pressure of ≥0.6 bar applied, measure the torque value at twothirds of the phase angle range using a torque sensor.
Intake Cam Phaser Assembly: ≤1.5 N·m
Exhaust Cam Phaser Assembly: ≤2.5 N·m Potential Impact:
Excessive friction torque may result in slower product response.
e. Phase Angle Test Requirement:
With the gear fixed, apply 1 bar oil pressure and measure the phase angle using an angle encoder.
Potential Impact:
A phase angle outside the specified range may trigger an ECU fault warning.
f. Leakage Rate Test Requirement:
With the gear fixed, apply 1 bar oil pressure and measure the flow rate using a flow meter.
Potential Impact:
Excessive leakage may cause slower response or lead to product failure.
